webpack工具学习 构建简单vue项目（不依赖vue-cli） webpack4.0

目的用webpack构建简单前端项目

1.npm init   (npm init -y)  形成package.json

2.npm install --save-dev webpack  形成 node_modules

3.项目路径dist--index.html   src---index.js----test.less    webpack.config.js

4.webpack.config.js配置

const path = require('path');

module.exports = {
    entry:'./src/index.js',
    output: {
        filename: 'bundle.js',
        path: path.resolve(__dirname,'dist') //解析到哪个目录
    },
    module: {
        rules: [
            {
                test:/\.less$/,
                use:[
                    {
                        loader:"style-loader"
                    },
                    {
                        loader:"css-loader"
                    },
                    {
                        loader:"less-loader"
                    }
                ]
            }
        ]
    },
    devServer: {
        contentBase:'./dist',
        watchContentBase:true
    }
}

5.运行webpack过程中提示安装webpack-cli  安装后package.json

{
  "name": "webpack-config",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "dev": "webpack-dev-server --mode development",
    "build": "webpack --mode production"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "css-loader": "^0.28.11",
    "less": "^3.0.4",
    "less-loader": "^4.1.0",
    "node-less": "^1.0.0",
    "style-loader": "^0.21.0",
    "webpack": "^4.8.3",
    "webpack-cli": "^2.1.3",
    "webpack-dev-server": "^3.1.4"
  },
  "dependencies": {}
}

webpack4.0以上版本支持mode  配置以上scripts里面指定运行环境

6.自动刷新  用到webpack-dev-server,进行相关配置 

7.安装  vue依赖相关  babel和vue系列

{
  "name": "webpack-config",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "dev": "webpack-dev-server --mode development",
    "build": "webpack --mode production"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "babel-core": "^6.26.3",
    "babel-loader": "^7.1.4",
    "babel-plugin-transform-runtime": "^6.23.0",
    "babel-preset-es2015": "^6.24.1",
    "babel-preset-stage-0": "^6.24.1",
    "babel-runtime": "^6.26.0",
    "css-loader": "^0.28.11",
    "extract-text-webpack-plugin": "^4.0.0-beta.0",
    "file-loader": "^1.1.11",
    "html-webpack-plugin": "^3.2.0",
    "less": "^3.0.4",
    "less-loader": "^4.1.0",
    "node-less": "^1.0.0",
    "optimize-css-assets-webpack-plugin": "^4.0.1",
    "style-loader": "^0.21.0",
    "vue": "^2.5.16",
    "vue-hot-reload-api": "^2.3.0",
    "vue-html-loader": "^1.2.4",
    "vue-loader": "^14.0.3",
    "vue-style-loader": "^4.1.0",
    "vue-template-compiler": "^2.5.16",
    "webpack": "^4.8.3",
    "webpack-cli": "^2.1.3",
    "webpack-dev-server": "^3.1.4"
  },
  "dependencies": {}
}

8.生成html文件  用到插件html-webpack-plugin   进行相关配置

9.想要css分离和压缩  用到插件extract-text-webpack-plugin   optimize-css-assets-webpack-plugin  进行相关配置   中途执行的时候有报错  根据报错提示一步步解决  搜索解决方案都能解决

10最后贴上webpack配置代码

const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');  //生成html文件  并引入css  js
const ExtractTextPlugin = require("extract-text-webpack-plugin"); //将css文件分开打包的插件
const OptimizeCSSPlugin = require('optimize-css-assets-webpack-plugin'); //压缩css文件

module.exports = {
    entry:'./src/index.js',
    output: {
        filename: 'bundle.js',
        path: path.resolve(__dirname,'dist') //解析到哪个目录
    },
    resolve:{
        extensions: ['.js', '.vue', '.json'],  //可以省略这些文件的扩展名
        alias:{
            'vue$':'vue/dist/vue.esm.js'    //vue默认读取运行时文件  运行时编译，通过配置读取全文件，包括编译器和运行时编译
        }
    },
    module: {
        rules: [
            {
                test:/\.vue$/,
                loader: 'vue-loader',
                options: {
                    loaders: {
                        less: ExtractTextPlugin.extract({ fallback: 'vue-style-loader', use: 'css-loader!less-loader' }),
                        css: ExtractTextPlugin.extract({ fallback: 'vue-style-loader', use: 'css-loader' })
                    }
                }
            },
            {
                test:/\.js$/,
                use:[
                    {
                        loader: 'babel-loader'
                    }
                ]
            },
            {
                test:/\.less$/,
                use: ExtractTextPlugin.extract({//use:指需要什么样的loader去编译文件,这里由于源文件是.css所以选择css-loader
                    fallback: "style-loader",//fallback:编译后用什么loader来提取css文件
                    use: "less-loader!css-loader"//publicfile:用来覆盖项目路径,生成该css文件的文件路径
                })
                // use:[
                //     {
                //         loader:"style-loader"
                //     },
                //     {
                //         loader:"css-loader"
                //     },
                //     {
                //         loader:"less-loader"
                //     }
                // ]
            }
        ]
    },
    devServer: {
        contentBase:'./dist',
        watchContentBase:true
    },
    plugins: [
        new HtmlWebpackPlugin({
            template:'./index.html',
            title:'index',
           // filename:'index.html',
            inject:true,
           // chunks:['main']
           hash:true //增加hash值  防止缓存
        }),
        new ExtractTextPlugin('css/index.css'),    //指定css打包路径
        new OptimizeCSSPlugin({                       //压缩css
          cssProcessorOptions: {
            safe: true
          }
        })
    ]
}

代码量不大  但是自己从中学到了挺多东西，记录下来   后面dist文件都是build出来的

参考https://zhuanlan.zhihu.com/p/27663434 [译]使用Webpack提高Vue.js应用程序的4种方式

https://www.cnblogs.com/wonyun/p/6030090.html html-webpack-plugin详解